Details

Autor(en) / Beteiligte

• Stoyanovsky, D. A.
• Sparvero, L. J.
• Amoscato, A. A.
• He, R. R.
• Watkins, S.
• Pitt, B. R.
• Bayir, H.
• Kagan, V. E.

Titel

Improved spatial resolution of matrix-assisted laser desorption/ionization imaging of lipids in the brain by alkylated derivatives of 2,5-dihydroxybenzoic acid

Ist Teil von

• Rapid communications in mass spectrometry, 2014-03, Vol.28 (5), p.403-412

Ort / Verlag

England: Blackwell Publishing Ltd

Erscheinungsjahr

2014

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• RATIONALE Matrix‐assisted laser desorption/ionization (MALDI) is one of the major techniques for mass spectrometry imaging (MSI) of biological systems along with secondary‐ion mass spectrometry (SIMS) and desorption electrospray mass spectrometry (DESI). The inherent variability of MALDI‐MSI signals within intact tissues is related to the heterogeneity of both the sample surface and the matrix crystallization. To circumvent some of these limitations of MALDI‐MSI, we have developed improved matrices for lipid analysis based on structural modification of the commonly used matrix 2,5‐dihydroxybenzoic acid (DHB). METHODS We have synthesized DHB containing ‐C6H13 and ‐C12H25 alkyl chains and applied these matrices to rat brain using a capillary sprayer. We utilized a Bruker Ultraflex II MALDI‐TOF/TOF mass spectrometer to analyze lipid extracts and tissue sections, and examined these sections with polarized light microscopy and differential interference contrast microscopy. RESULTS O‐alkylation of DHB yields matrices, which, when applied to brain sections, follow a trend of phase transition from crystals to an oily layer in the sequence DHB → DHB‐C6H13 → DHB‐C12H25. MALDI‐MSI images acquired with DHB‐C12H25 exhibited a considerably higher density of lipids than DHB. CONCLUSIONS Comparative experiments with DHB and DHB‐C12H25 are presented, which indicate that the latter matrix affords higher lateral resolution than the former. Copyright © 2014 John Wiley & Sons, Ltd.